Shoe sole attaching machine



July 22, 1958 E. HAAs SHOE SOLE ATTACHING MACHINE Filed May 6, 1955 4Sheets-Sheet 1 FDGAA HAAS 15%/ A TTOR/VKS.

July 22, 1958 E. HAAs SHOE SOLE ATTACHIFNG MACHINE 4 Sheets-Sheet 2Filed May 6, 1955 SAFETYy dvolv /477-O/Q/VEVS July 22, 1958 E. HAAS SHOESOLE ATTACHING MACHINE Filed May 6, 1955 v 4 Sheets-Sheet 3 TTO/P/V-YS.

July 2z, 195s E. HMS 2,843,864

SHOE SOLE ATTACI-IING MACHINE Filed May 6, 1955 4 Sheets-Sheet 4 /N VEA/To@ l 50cm/P HAA s United States Patent Q m SHOE SLE ATTACHING MACHINEEdgar Haas, New York, N. Y., assigner to Herman Schwabe, Inc., New York,N. Y., a corporation of New York Application May 6, 1955, Serial No..506,443

9 Claims. (Cl. 12-36) This invention relates to shoe machines, and moreparticularly to hydraulic sole attaching machines.

Machines for attaching shoe soles by means of adhesive are alreadyknown. There are usually a plurality of work stations, most commonly twostations, handled in alternation by a single operator. The adhesive usedsets upon the application of sutlicient pressure over a specied time.Modern adhesives are fast and sensitive, and the manufacturers usuallyspecify not only an optimum pressure but also an optimum time, which mayrange from, say, tive to fifteen seconds, depending on the particularadhesive. Stations interconnected to work automatically in alternation,with a timing depending wholly on the speed or judgment of the operator,fail to make best use of the up-to-date improvements in adhesives.

The primary object of the present invention is to gener` ally improvehydraulic sole attaching machines. A more specific object is to providea machine with a plurality of stations, say two, the operation and thetiming or dwell of each of which is independent of the operation of theother. A further object is to provide for accurate timing of the dwell,independently of the judgment of the operator. For this purpose areadily and accurately adjustable timer is employed, and l prefer to usea timer of the clock type having a range of from, say, zero to thirtyseconds, and a scale which is accurate to a fraction of a second. Anancillary object is to provide a solenoid controlled valve arrangementwhich will not require the switching mechanism of the timer to handlemore than a small current.

Still another object is to provide for safety release of the clampingstations.

Although the operation of one station is independent of another, theywill ordinarily be operated in displaced time relation, because a singleoperator is attending the ditferent stations. Preferably a single orcommon tank, pump, pressure relief valve, and spring operatedaccumulator are all used in common for the different stations. A furtherobject of the invention is to prevent the pressure on a rst clamped shoefrom being relieved or lessened upon initiation of the clampingoperation on a second shoe.

To accomplish the foregoing objects, and others which will hereinafterappear, my invention resides in the shoe sole attaching machineelements, and their relation one to another, as are hereinafter moreparticularly described in the following specification. The specificationis accompanied by drawings, in which:

Fig. 1 is a front elevation of a machine embodying features` of myinvention;

Fig. 2 is a section through a solenoid-controlled, pilotoperated,four-way valve used in the machine, drawn to enlarged scale;

Fig. 3 is a view of the sub-plate of the valve shown in Fig. 2, drawn tosmaller scale than in Fig. 2;

Fig. 4 is a wiring diagram explanatory of a detail of the invention;

2,843,864 Patented July 22, s

Fig. 5 is a partially schematic view explanatory of the invention;

Fig. 6 is a wiring and pipe diagram explanatory of the invention; and

Fig. 7 is a schematic view generally like Fig. 5, but showing a modifiedform of the invention.

Referring to the drawing, and more particularly to Fig. l, 'the machinethere shown comprises a base 1:2 which acts also as a tank for hydraulicfluid. This is surmounted by a frame comprising uprights 14 and a topbeam 16. The latter carries adjustable heel and toe posts for each of aplurality of stations. l prefer to employ two stations, as here shown.

One station is actuated by an hydraulic piston 0r plunger 20 which isshown down, and the other by piston or plunger 22 which is shown raised.The plungers have platens Z4 and 26, which in turn carry pad boxes 28and 30. These usually contain rubber molded to the shape of the bottomof the shoe. T he shoe upper is on a last, and the sole and the lastedupper are vertically compressed between the pad box at the bottom, andheel and toe posts at the top carried by the beam 16, as is indicated bythe shoe 32. The heel post 3d bears on the back cone of the last. Thetoe post is not shown in Fig. 1, but bears on the top of the toe portionof the lasted upper.

if desired the piston 20 and platen 2.4 may be provided with an arm 2lwhich rides in a mating guide groove or track in upright 14, therebyholding the platen in desired alignment relative to the heel and toeposts. Similarly the piston Z2 and platen 26 may have a guide arm 23. Ashelf 25 may be provided for the convenience of the operator.

ln the present machine the stations are independently movable undercontrol of separate foot treadles 40 and 42. Depression of a foottreadle causes its station to move from lowered or release position toupper or clamping position. The tank l2 is common to both stations, andhouses a common pump, and a common pressure relief valve, which may beadjusted by means of a handle 44. The resulting pressure may be read ona suitable pressure gauge 46. In a typical case the pump is capable ofbuilding up a pressure of say 1,000 lbs. per square inch, but thepressure relief valve may be set at a lower ligure, say 300 or 400pounds per square inch, depending on the recommendations of themanufacturer of the adhesive, and the experience of the shoemanufacturer.

The time during which each station remains clamped is independentlydetermined by timing devices, and in the present case l provideaccurately adjustable electrical timing clocks S0 and 52. These have asuitable range, which in the present case is from zero to thirtyseconds, and the scale is large and easily read so that the timers maybe set to a fraction of a second.

The head or beam 16 additionally carries a safety switch controlled by aconspicuous safety bar` 54. If this bar is touched, pressed or hit thestations are simultaneously released. g

The head 16 further carries the main motor starter for the motor whichdrives the hydraulic pump. This is shown at 56, and ordinarily is of thethree-phase type, and includes means for overload protection. The part58 is a shut-off valve for the pressure gauge 46.

Considering the machine in greater detail, and referring now to Fig. 5of the drawing, the single pump is shown at 60, and is preferablyimmersed in the tank of fluid as indicated at 62. The inlet is takenthrough a sieve 64, and is delivered to a spring accumulator 66, whichmay also be immersed in the fluid. The purpose and design of thisaccumulator are described in greater detail in my co-pending applicationentitled Hydraulic Sole Attaching Machine, Serial No. 419,989, filedMarch 31, 1954, now Patent No. 2,783,486 issued March 5,

1957. The pump output is also connected through pipe 68 to a pressurerelief valve '70, the control handle 44 of which is located in front ofthe machine for ready adjustment. Overflow from the relief valve isreturned to the main body of fluid 62 through a return pipe 72.,Thepump60 is driven by an electric motor 74.

The pressure fluid is connected through pipe '76 to a first valve 78 forcylinder 80 at one station, and to cylinder 82 for the other stationthrough a pipe 84 and valve 86. These valves are preferably solenoidactuated, asis indicated bythe solenoids 38 and 90. ln one position ofthe valve 78 the pressure fluid is connected through pipe 92 and checkvalve 94 to cylinder 80. ln the opposite position of the valve 78 thecylinder 80 is relieved through pipe 96, valve 78, and drain pipe 18,and it should be noted that this circuit bypasses the check valve 94.

The valve 78 may be described in greater detail with reference to Fig. 2of the drawing. It will be seen there that the valve is asolenoid-controlled and pilot-operated, four-way valve. The solenoid isshown at 88 and controls a plunger 102. Inasmuch as the solenoid currentis handled by the timer clock, and inasmuch as the main Valve issizable, it is preferred to boost the effect of the current handled bythe timer. This could be done electrically by using relays controlling alarge solenoid for moving the main spool 104 in the main valve housing106, but in the present case the magnication is obtained hydraulically,and for this purpose the solenoid may be small but controls a smallpilot spool 108 in a pilot valve housing 110. This in turn supplies someof the pressure fluid to one end or the other of the main spool 104,thus actuating the latter to one end position or the other. In theposition shown in Fig. 2 the solenoid is de-energized; its plunger israised; and pilot spool 108 is raised by spring 109.

Connections to the valve housing 106 are made through a sub-plate 114. Abottom or face View of this suhplate is shown in Fig. 3, referring towhich it may be explained that pressure fluid is suppliedthrough apressure port 116. A drainage or tank connection is made at 118. Thereis a separate drainage or tank connection for the pilot valve shown at120. There are two ports for connection to the hydraulic cylinder. Theport 122 goes directly to the cylinder, while port 124 is connectedthrough a check valve to the cylinder. Reverting now to Fig. 2, theports 116, 118 and 120 are indicated in dotted lines, while the ports122 and 124, also marked A and B, which are located in staggeredrelation behind the other ports, are indicated merely by center lines.

The valve body includes a passage (not shown) for high pressure fluidfrom the port 116 to the middle region of pilot spool 108. Sometimes aseparate pressure port is provided, but in -the present machine in whichthe pressure never drops below a value far in excess of what is neededto operate the pilot valve, the regular pressure port may be used forboth spools. The pressure tluid flows upward through passage 112, andthus holds the main spool 104 downward. The region below the main spoolis emptied through passage 126 and thence downward at the lower end ofpilot spool 108, and from there through a passage in the valve body (notshown), to the pilot drain port 120. With the main spool 104 in the downposition shown, the hydraulic lluid admitted at 1'28 is blocked by themiddle part 130 of spool 104. The cylinder is drained through the A port122 leading to port 132 and communicating through the small diameterpart 134 of the spool to port 136 and thence tothe drain port or tankconnection 118.

When the solenoid 88 is energized its core 102 is pulled down and movesthe pilot spool 108 to a down position, at which time pressure Huidflows from the center port 138 through the passage 126 to vthe lower endof main spool 104, which then is raised. At the same time the passage112 is connected to the region `above the upper end of spool 108, thuspermitting discharge of fluid through a passage in the valve body, notshown, to the pilot drain port 120.

When the main spool 104 has been moved to its up position the pressurefluid flows from port 128 through the reduced diameter part 140 of thespool to the port 142, which communicates with the port B indicated bycenter line 124. Thus high pressure Huid ows through the check valve 94(Fig. 5) to the cylinder 80, until the shoe is raised and clamped.Meanwhile the port 132 (Fig. 2) communicating with port A is closed bythe large diameter part 130 of the spool 104.

Reverting now to Fig. 5, the valves 78 and 86 are like that shown inFig. 2 of the drawing. The valve and pipe arrangement for the cylinder82 is symmetrical or corresponds to that for cylinder 80, and no furtherdescription is believed required. It will also be lunderstood that thecheck valve 94 prevents any lessening of pressure in clamp cylinder whenpressure is irstapplied to clamp cylinder 82, and conversely thecheckvalve 144 of clamp cylinder 82 prevents lessening of pressure inthe latter when clamp cylinder 80 is first actuated.

Because of the check valves it is not possible to drain the cylindersthrough the B ports, and it is for this reason that separate A ports areprovided, vwith connections which bypass the check valves, thus drainingthe cylinder.

The system may be additionally described with reference to Figs. 4 and 6of the drawing. Referring first to Fig. 4, the motor '74 which drivesthe pump is preferably a three-phase motor operating at 220, 440 or 550`volts, depending on the preference orrequirements of the shoemanufacturer using the machine. The motor control 56 may beconventional, and preferably includes overload protection meansindicated at 150. One phase of the three-phase supply is tapped for thecontrol mechanism of the machine. The parts of this mechanism arepreferably standardized to operate at volts, and I therefore provide astep-down transformer indicated at 152. This has suitable taps to supplyllO volt outputat L1, L2, whether the three-phase input is at 220, 440,or 550 volts.

Referring now to Fig. 6, the transformer output `is indicated at L1, L2.The timing clocks are shown at 50 and S2, the safety switch at 54, andthe solenoids at 88 and 90. These control the pilot valves symbolized at158 and 160, which in turn control the main valves 78 and 86. The pump60, accumulator 66, pressure relief valve 70, check valves 94 and 144,cylinders 80 and 82, and treadles 40 and 42 all correspond to thesimilarly numbered parts previously described. Treadle vv40 controls aswitch 162, while treadle 42 controls a switch 164.

The timers S0 and 52 are operated by clock motors 166 and 168. They alsoinclude a number of contacts or switches and a solenoid 170 (and 172)for shifting the contacts. The particular timer here shown has fourmovable contacts, but only two are required and used for the presentcircuit. The particular clock shown is the HP-2 series made by EagleSignal Corporation of Moline, illinois, under the name Cycl-Flex. Thesecome in different ranges of time from thirty seconds to a number ofhours, and in the present case the thirty second timer is used, withscale markings of one-half second.

There are eight terminals on the timer, as marked. The timer may bearranged for maintained contact or for momentary contact, and in thepresent case is `wired for momentary contact, so that the treadleneedonly be touched but not held down. Solenoid 170 raises ,the righthand switches shown below the solenoid. The left hand switches aremechanically operated by the clock motor.

Stepping on treadle 40 energizes solenoid 170, thus I valve solenoid 88,and so starts the clamping operation.

It also closes its upper switch at clock terminal 6, and so starts theclock motor 166, and closes a holding circuit for the solenoid.

More specifically, when treadle 40 is depressed current ows fromL1`through solenoid coil 170 and conductor 174, switch 162, conductor176, conductor 178 to L2. This closes the contact at clock terminal 6,thus starting the clock motor 166, the circuit being from L1 through theclock motor, the closed contact at 6, conductor 180, switch 54,conductor 182, back to L2. Solenoid 170 also closes the switch toterminal 8, thereby energizing the valve control solenoid 88. Thecircuit for this is from L1 through conductor 184 to solenoid 88 andback through conductor 186 to clock terminal 8 through the closed switchto terminal 5 and terminal 4 and thence through conductor 178 to L2. Theenergization of solenoid 88 changes the valves from release to clampingposition, and this is shown in the right-hand part of the drawing forcylinder 82. More specifically, the pilot valve 158 is changed to thecondition shown at 160, and this changes the main valve 78 to theposition shown at 86, at which time high pressure fluid ows from thepump 60 and accumulator 66 through pipe 188, valve 86, check valve 144,and pipe 190 to the clamp cylinder.

Closing of the switch at terminal 6 also provides a holding circuit tokeep the solenoid 170 energized even though the treadle 40 is releasedimmediately after it has been depressed. Specifically, current flowsfrom L1 through solenoid coil 170 through the switch at terminal 1 toterminal 2 and thence through the switch at terminal 6 to conductor 180,switch 54, conductor 182, and back to L2.

The position of the switches in the clock during the clamping operationis shown in the righthand clock. When the time for which the clock isadjusted :has run out the clock mechanism opens the switch at clockterminal 1 momentarily, thereby opening the holding circuit throughsolenoid 170 and thus opening the switches at terminals 6 and 8. Thisalso stops the clock motor. The parts are all reset to the conditionshown in the lefthand clock.

From inspection of the diagram it will be seen that depression of thesafety switch 54 opens the return circuit from the clock solenoids tothe line L2, and this corresponds to running out of the time on theclocks, which causes de-energization of the solenoids 88 and 90, andimmediate release of the clamping pressure at both stations.

When the solenoid 90 is de-energized the pilot valve 160 changes to thecondition shown at pilot valve 158, which changes the main valve 86 tothe condition shown in main valve 78, at which time clamp cylinder 80 isfree to discharge through pipes 192 and 194 and thence through mainvalve 78 to discharge port T emptying into the tank.

The foregoing system may be described as being electro-hydraulic.However, it is also possible to employ features of the invention whileusing a system which is partially mechanical, and in Fig. 7 of thedrawing I show such a system, which system may be described as beingelectro-mechanical-hydraulic. In Fig. 7 many parts correspond to thoseshown in Fig. 5, and have been similarly numbered with primed numerals.This applies to the clamp cylinders 80 and `82 moving pad boxes 28 and30 with lasted shoes upward against heel and toe posts. Similarly thereare accurate timer clocks 50 and 52', and a safety release bar 54', aswell as a motor starting box 56. The submerged pump 60', springaccumulator 66', pressure relief valve 70', and pump motor 74 allcorrespond to those previously described. In the present case, however,instead of two separate treadles working electrical switches, there is arelatively large double treadle 200, pivoted in front of the machine at202, and connected by a link 204 to a lever 206 pivoted on a shaft 208.The shaft passes into the base or tank, and carries a lever 210 which isdisposed between projections 212 and 214 of the spools of main valves216 and 218. Depression of the left part of treadle 200 moves spool 212to the left without, however, shifting spool 214. This causes valve 216to supply high pressure fluid to clamp cylinder Similarly, depression ofthe righthand side of the treadle moves spool 214 to the right withoutaffecting spool 212, and thus causes main valve 218 to feed highpressure fluid to the clamp cylinder 82.

Considering the arrangement in greater detail, high pressure fluid isconnected to the main valves through pipe 220 at ports 222 and 224.Discharge to the tank is through ports 226 and 228. Valve 216 isconnected to cylinder 80 through pipe 230 and check valve 232. The checkvalve is bypassed by means of a pilot operated check valve 234 having adischarge port 236 leading to the tank. The system further comprises asolenoid operated pilot valve 238 to which high pressure fluid isconnected by pipe 240. There is a discharge port 242 leading back to thetank.

The system further comprises a micro switch 244 which is opened by theguide arm 246 when the clamp cylinder is released, but which closes andremains closed when the clamp cylinder is above its lowermost position.It will be understood that the righthand side of the system issymmetrical with the lefthand side, and `has corresponding parts. Someof the wiring (at 244 .and 250) has been omitted at the righthand sideto simplify the drawing.

The operation is as follows: When the spool 212 of main valve 216 ismoved to the left, high pressure fluid ows from pipe 220 through port222 and thence through pipe 230 and check valve 232 to the clampcylinder 80. At this time the valves 234 and 2318 are both closed. Asthe clamping operation begins the switch 244 is closed, thereby startingthe timer S0.

When the time runs out a circuit through conductors 250 is energized,thus actuating the solenoid of pilot valve 238, which admits highpressure fluid to the left end of spool 212, thus shifting the spool tothe right. This cuts off the feed of high pressure iiuid to the clampcylinder, and supplies it instead to the pilot check valve 234, whichthereupon is shifted from closed to open position, thus permitting uidto drain from cylinder 80 to the discharge port 236, and so back to thetank. When the platen has descended the switch 244 is opened, therebycle-energizing the timer 50 until the next clamping operation begins.

The switch connections inside the timer may be modied slightly from whatis shown in Fig. 6, this being done because switch 244 remains closed,thus ycorresponding to continued depression of the treadle in Fig. 6,and this eliminates the need for a holding circuit. I have not shown theinternal wiring for the clock 50', it being understood that this issupplied with the clock as manufactured. The clock is made to be useablewith either a momentary contact trip, as in Fig. 6, or a maintainedcontact, as in Pig. 7.

It is believed that the construction and operation of my improvedhydraulic sole attaching machine, as well as the advantages thereof,will be apparent from the foregoing detailed description. The operation,and the timing or dwell, of each station is independent of the operationof the other. The timing of the dwell or clamp period is accuratelycontrolled to even a fraction of a second. Simultaneous release of allstations is provided, for safety. A spring accumulator affords rapidrise of the shoe to clamping position, thus freeing the hands of theoperator. However, the initiation of a clamping operationat one stationdoes not relieve or lessen the pressure on a shoe already clamped inanother station.

It will also-be apparent that while I have shown and described myinvention in several preferred forms, Kchanges may be made in thestructures shown without departing .from the scope of the invention, assought to be delined in the vfollowing claims.

l claim:

1. A shoe sole attaching machine comprising a plurality of clampcylinders and clamp pistons therein each independently movable between arelease position for loading or removal of a shoe and a clampingposition for securinga sole to a shoe, a common tank `for hydraulicfluid, a common pump, a plurality of solenoid controlled valves eachhaving the housing of a four-way valve but a special spool forcontrolling the flow of fluid to the cylinders, each four-way valvehaving both its cylinder ports connected by separate pipes to one end ofits associated clamp cylinder, and eachhaving a check valve in one ofsaidpipes, a plurality of electrical timers Veach having a scale for.adjustment in seconds, a plurality of switches, each switch beingassociated with a timer and a four-way valve and a clamp cylinder, eachswitch serving to start its associated timer and solenoid and clampcylinder, circuitry whereby running out ,of any one of said timersshifts its associated solenoid and terminates the clamping operation ofits associated valve and cylinder.

2. A shoe sole attaching machine comprising a plurality of clampcylinders and clamp pistons therein each independently movable between arelease vposition for loading o-r removal of a shoe and a clampingposition for securing a sole to a shoe, a common tanlcfor hydraulic uid,a common pump, a common spring operated accumulator connected to thepump, a plurality of solenoid controlled valves each having the housingof a four-way valve but a special spool for controlling the ow of fluidto the cylinders, each four-way valve having both its cylinder portsconnected by separate pipes to one end of its associated clamp cylinder,and each having a check valve in one of said pipes, a plurality ofelectrical'tirners each having a scale for adjustment in seconds,aplurality of switches, each switch being associated with a timer and afour-way valve and a clamp cylinder, each switch serving to start itsassociated timer and solenoid and clamp cylinder, circuitry wherebyrunning out of any one of said timers shifts its associated solenoid andterminates the clamping operation of its associated valve and cylinder.

3. A shoe sole attaching machine comprising a plurality of clampcylinders and clamp pistons therein each independently movable between arelease position for loading or removal of a shoe and a clampingposition for securing a sole to a shoe, a common tank `for hydraulicl'luid, a comm-cn pump, a plurality of solenoid controlled valves eachhaving the housing of a four-way valve'but a special spool forcontrolling the ilow of fluid to the cylinders, each four-way valvehaving both its cylinder ports connected by separate pipes to one end ofits associated clamp cylinder, and each having a check valve in one ofsaid pipes, a plurality of electrical timers each having a scale foradjustment in seconds, a plurality of switches, each switch beingassociated with a timer and a four-way valve and a clamp cylinder, eachswitch serving to start its associated timer and solenoid and clampcylinder, circuitry whereby running out of any one of said timers shiftsits associated solenoid and terminates the clamping operation of itsassociated valve and cylinder, and a single safety switch in saidcircuitry for simultaneously terminating the clamping operation loi allof said cylinders at any time.

4. A shoe sole attaching machine comprising a plurality of clampcylinders and clamp pistonsthereon each independently movable between arelease position for loadingor removal of a shoe and a clamping positionfor securing .a sole to a shoe, a common tank for vhy- 'draulic fluid, acommon pump, a'cornmon spring operated accumulatorvconnected to thepump, a plurality of solenoid controlled valves each having the housingOf'a four-Way valve but a special spool for controlling the flow oftluid to the cylinders, eachfour-way valve having both its'cylinderports connected by separate pipes to one 'end of its .associated clampcylinder, and each having a vcheck valve" in one of said pipes, aplurality of electrical timers each having a scale for adjustment inseconds, a plurality ot switches, each switch being associated with aVtimer and a four-way'valve and a clamp cylinder, each switch servingrto start its associated timer and solenoid and clamp cylinder, circuitrywhereby running out 'of any one of said'timers shifts itsassociatedsolenoid and terminates theclamping operation of itsassociated valve and cylinder, and a'single safety switch in saidcircuitry Vfor simultaneously terminating the clamping operation of allof said cylinders at any time.

5. A shoe sole attaching machine comprising a pluralitylof clampcylinders and clamp pistons therein each independently rnovable betweena release position for -loading 'or removal of a shoe and a clampingposition for securing a sole to a shoe, a common tank for hy- 'draulicfluid, a common pump, a plurality of solenoid controlled valves eachhaving thehousing of a four-Way valvebut-a special spool'for controllingthe ow of uid to kthe cylinders, each four-way valve having both itscylinder vports connected by separate pipes to one-end 'of itsassociated clamp cylinder, and each having a check valvein one of saidpipes, a plurality of electrical timers veachhaving a scale'foradjustment in seconds, a plurality of switches, each switch beingassociated .with a timer and a four-way valve and a clamp cylinder, eachswitch serving to start its associatedtimer and solenoid and clampcylinder, circuitry whereby-running out of any one of said timers shiftsits associated solenoid and terminates the clamping operation of itsassociated valve and cylinder, said Vcheck valves assuring that thepressure on a clamped shoe willnot be relieved upon initiation ofa-clamping operation on another shoe, said four-way valve being so'designed aste-bypass the check valve on termination of a clampingoperation.

6. A shoe sole attaching machine comprising -aplurality-of clampcylinders and clamp pistons thereineaeh independently movable between arelease position-for loading or removal of a shoe anda clamping positionfor `securing a sole to a shoe, a common tank for hydraulic fluid, acommon pump, a common spring operated accurnulatorL connectedrto thepump, a plurality of solenoid controlled valves-each having the housingof -a four-.way valvetbut, a special spoolforcontrolling the flow oflluid tothe cylinders, each four-way valve having both' its cylinderports connected by separate pipes to=one-end of its associated clampcylinder, and each having a check valvein one of said pipes, a pluralityof electrical timers each having a scale for adjustment in seconds,aplurality of switches, each switch being associated .witha timer and afour-way valve and-aclamp cylinder, each switch serving to start itsassociated timer and solenoid and clamp cylinder, circuitry wherebyrunning out of any one of said timers shifts its associated solenoid andtermi- ^nates-the clamping operation of itsassociated valve and"cylinder, said check valves assuringthat the pressure on a clamped shoewill not berelieved :upon .initiationof a clamping operationon anothershoe, said four-way valve 'being-so designed as tobypass the checkvalveon termination of-a clamping operation.

7. A shoe sole attaching machinecomprisinga plurality of .clampcylinders and clamp pistons therein each independently movable` betweena release position for loading or ,removal ofa shoe. and aclampingposition for :securing a sole to a shoe, a common tankforfhydraulic fluid, acommon-pumpa plurality of solenoidfcontrolledvalves each having the housing of a four-way valve but a special spoolfor controlling the flow of lluid to the cylinders, each four-way valvehaving both its cylinder ports connected by separate pipes to one end ofits associated clamp cylinder, and each having a check valve in one ofsaid pipes, a plurality of electrical timers each having a scale foradjustment in seconds, a plurality of switches, each switch beingassociated with a timer and a four-Way valve and a clamp cylinder, eachswitch serving to start its associated timer and solenoid and clampcylinder, circuitry whereby running out of any one of said timers shiftsits associated solenoid and terminates the clamping operation of itsassociated valve and cylinder, said check valves assuring that thepressure on a clamped shoe will not be relieved upon initiation of aclamping operation on another shoe, said four-way valve being sodesigned as to bypass the check valve on termination of a clampingoperation, and a single safety switch in said circuitry forsimultaneously terminating the clamping operation of all of saidcylinders at any time.

8. A shoe sole attaching machine comprising a plu rality of clampcylinders and clamp pistons therein each independently movable between arelease position for loading or removal of a shoe and a clampingposition for securing a sole to a shoe, a common tank for hydraulicfluid, a common pump, a common spring operated accumulator connected tothe pump, a plurality of solenoid controlled valves each having thehousing of a four-way valve but a special spool for controlling the flowof fluid to the cylinders, each four-way valve having both its cylinderports connected by separate pipes to one end of its associated clampcylinder, and each having a check valve in one of said pipes, aplurality of electrical timers each having a scale `for adjustment inseconds, a plurality of switches, each switch being associated with atimer and a four-way valve and a clamp cylinder, each switch serving tostart its associated timer and solenoid and clamp cylinde-r, circuitrywhereby running out of any one of said timers shifts its associatedsolenoid and terminates the clamping operation of its associated valveand cylinder, said check valves assuring that the pressure on a clampedshoe will not be relieved upon initiation of a clamping operation onanother shoe, said four-way valve being so designed as to bypass thecheck valve on termination of a clamping operation, and a single safetyswitch in said 10 circuitry for simultaneously terminating the clampingoperation of all of said cylinders at any time.

9. A shoe sole attaching machine comprising a plurality of clampcylinders and clamp pistons therein each independently movable between arelease position for loading or removal of a shoe and a clampingposition for securing a sole to a shoe, a common tank lfor hydraulic:`

iuid, a common pump, a common adjustable pressure relief valve, a commonspring operated accumulator connected to the pump, a plurality ofsolenoid controlled valves each having the housing of a four-way valvebut having a special spool for controlling the ow o-f fluid to thecylinders, each four-way valve having both its cylinder ports connectedby separate pipes to one end. of its associated clamp cylinder, and eachhaving a check valve in one of said pipes, a plurality of electricaltimers each having a scale for adjustment in seconds, a plurality offoot pedal controlled switches, each switch being asso ciated with oneof said timers and solenoids and clamp cylinders, Icircuitry wherebyrunning out of any one of said timers shifts its associated solenoid andterminates the clamping operation of its associated valve and cylinder,said check valves being disposed between each four-way valve and itsclamp cylinder whereby the pressure on a clamped shoe will not berelieved upon initiation of a clamping operation on another shoe, thespool of said four-way valve being so designed and related to itshousing as to bypass its check valve on termination of a clampingoperation, and to then block the pump in order to apply pressure toanother clamp cylinder or/and to said accumulator, and a single safetyswitch in said circuitry for simultaneously terminating the clampingoperation of all of said cylinders at any time.

References Cited in the le of this patent UNITED STATES PATENTS1,540,181 Olson June 2, 1925 2,486,537 Senileben Nov. 1, 1949 2,591,800Gardiner Apr. 8, 1952 2,633,102 Baldwin et al. Mar. 31, 1953 2,639,585Camerota May 26, 1953 2,698,632 Margrave et al. Ian. 4, 1955 2,716,766Gulbrandsen Sept. 6, 1955

